Changing your Facebook profile picture varies depending on whether you're accessing the service through the Facebook website or the mobile app. Whatever your platform, you can choose either an existing photo, take a new photo or choose one in which you are tagged.
Changing Your Profile Picture on the Facebook Website
To change your profile picture on the Facebook website, log in to your account and hover your mouse over your current picture. Click "Update Profile Picture" and select the location from which you want to obtain the picture. You can select from existing Facebook pictures you're tagged in, upload a new photo from your computer or take a new photo with your computer's webcam, if available. Once you've selected your photo, crop it and click "Save Profile Picture."
Changing Your Picture in the Facebook App for iOS
To change your profile picture on the Facebook mobile app for iOS devices, log in to Facebook and tap your current profile picture. Tap "Choose From Photos" to select a new profile picture from existing Facebook photos, including those you're tagged in. Alternatively, tap "Upload Photo" to upload a new picture from your camera roll. Crop and reposition the new photo and tap "Done" when you're satisfied with the results.
Changing Your Picture in the Facebook App for Android
If you want to upload a new photo using the Facebook app for Android, tap your current profile picture and select "Edit Profile Picture." Select a photo from your library or tap the "Camera" icon to take a new one. If you take a new picture with your camera, tap the "Menu" icon after you're finished and select the photo in your library. Crop the photo and press "Done" when you're satisfied with the results.
If you want to select a new profile picture from existing Facebook photos, navigate to the Facebook photo you want to use, tap the three-dot "Menu" icon or your phone's "Menu" button and then tap "Make Profile Picture." On certain devices, you may have to tap "More" before you can see the Make Profile Picture menu option. Crop your photo and tap "Done" when you're satisfied with the results.